Tailored interventions for motivating smoking cessation: using placebo tailoring to examine the influence of expectancies and personalization.

The present study examined mechanisms underlying the effectiveness of tailored interventions for motivating smoking cessation. The study used a placebo-tailoring design to test whether the efficacy of tailoring was due, in part, to personalized features in addition to the theoretically based content. Two hundred forty adult smokers were randomized to 1 of 3 conditions: standard booklet, minimally personalized booklet, or extensively personalized booklet. The interventions varied in their degree of ostensible tailoring, yet the actual smoking-related content of the booklets was identical. A dose-response relationship was hypothesized, with the greatest apparent tailoring producing the most positive outcomes. This pattern was found for evaluation of the booklets, with trends for readiness to change and self-efficacy increases. Moreover, as hypothesized, the effect of the interventions on readiness was moderated by participants' expectancies about tailoring.